KR102303009B1 - How to operate a blast furnace - Google Patents

Abstract

Provided is a blast furnace operation method capable of controlling the component concentration of a blast furnace raw material to a target component concentration even if the component concentration of the sinter raw material fluctuates. A blast furnace operation method for charging a blast furnace raw material including raw sintered ore, lump iron ore, and auxiliary materials into a blast furnace, comprising: a sintering step of sintering the sintered raw material to form a sinter cake; A cooling process of cooling the sintered ore, a quartering process of dividing the cooled sintered ore into sintered ore and return ore, and measurement of measuring the concentration of at least one component among the cooled sintered ore, sintered ore and semi-ore It has a process and an adjustment process of adjusting the compounding quantity of sintered ore, lump iron ore, and auxiliary material contained in a blast furnace raw material, In an adjustment process, the compounding quantity of a blast furnace raw material is adjusted using the component concentration measured in the measuring process.

Description

How to operate a blast furnace

The present invention relates to a blast furnace operation method for adjusting the blending amount of blast furnace raw materials, and more specifically, to a blast furnace operation method for measuring the component concentration of sintered ore, a blast furnace raw material, and adjusting the blending amount of the blast furnace raw material using the component concentration it's about

In the blast furnace ironmaking method, iron-containing raw materials such as sintered ore, lump iron ore, and pellets are mainly used as the iron source as the blast furnace raw material at present. Here, the sintered ore includes, in addition to iron ore having a particle size of 10 mm or less, miscellaneous iron sources such as various dusts generated in the steel mill, and CaO-containing raw materials such as limestone, quicklime, and slags, and silicate or serpentine. _{, SiO 2} source or MgO source composed of dolomite or refined nickel slag, and solid fuel (carbon material), which is a coagulation material composed of powdered coke or anthracite, mixed and granulated while adding moisture with a drum mixer, It is a kind of calcined agglomerated ore.

In recent years, the concentration of iron contained in the raw material for sinter, which is a raw material for sinter ore, is decreasing, instead, the concentration of _{gangue components such as SiO 2} and Al ₂ O ₃ is increasing, and even in the same type of ore, ships at the time of import The component concentration of the calculated ore is unstable to such an extent that the component concentration may differ for each.

Variation in the component concentration in the raw material for sinter leads to variation in the component concentration of the sintered ore, which is a natural product. In general, the concentration of the components of the raw material charged into the blast furnace is always controlled for reasons such as control of the quality of the slag. When a certain component concentration becomes high, in order to weaken it, since it is necessary to add another component as an auxiliary material, it is necessary to detect the change of the component concentration of a sintered ore, a lump iron ore, and a pellet urgently. Since lump iron ore and pellets are properties themselves, the component concentration is analyzed during shipment, etc., but the analysis of the component concentration on-line regarding the current sintered ore is not performed, and the frequency is very low. There is no analysis of the component concentration outside.

For example, if the component concentration of the blast furnace raw material is fluctuated due to a change in the component concentration of the sintered ore and is greatly separated from the target component concentration, and thus the viscosity of the slag is deteriorated, the molten iron temperature may be increased to maintain the viscosity of the slag. There is a need. The deterioration of the viscosity of the slag leads to deterioration of the slag discharge in the lower portion of a blast furnace, and accordingly, the gas flow is inhibited and the air permeability is deteriorated. There is a possibility that it may be necessary to increase the amount of coke to be added. In this way, when the component concentration of the blast furnace raw material greatly deviates from the target component concentration, the blast furnace operation becomes unstable, and various countermeasures are required.

As a technique for grasping the quality of sintered ore, for example, in Patent Document 1, the reduction property and reduction degradation property of the original sintered ore are predicted from the filling condition of the sinter raw material, and the blending ratio of the blast furnace raw material A technique of adjusting the blast furnace raw material by adjusting the blending of the sinter raw material rather than adjusting the sintering furnace is disclosed.

Patent Document 2 discloses a technique of measuring FeO of the original sintered ore and adjusting the coagulant, granulated moisture, and amount of exhaust air of the raw material for sinter from the difference from the target target value. Moreover, in patent document 3, the technique of measuring FeO of an original sintered ore similarly, and adjusting the quantity of the city gas blown into a sintering machine from the difference with the target target value is disclosed.

Patent Document 4 discloses a technique for estimating the component of the original sintered ore from the components of the surface layer of the sintering raw material obtained by a laser-type component measuring device installed on the sintering machine and reflecting it in the mixing of the sintering raw material.

Japanese Laid-Open Patent Publication No. 10-324929 Japanese Laid-Open Patent Publication No. 57-149433 Japanese Laid-Open Patent Publication No. 2011-038735 Japanese Laid-Open Patent Publication No. 60-262926

However, what is disclosed in Patent Documents 1 to 4 is a technique of measuring a certain component concentration in the sintered ore, and adjusting the raw material for sinter using the measured component concentration, or adjustment of the manufacturing conditions of the sintered ore. It is a technique to do In Patent Documents 1 to 4, it is not disclosed at all to adjust the blending amount of the blast furnace raw material charged into the blast furnace using the measured component concentration of the sintered ore. Since the component concentration of sintered ore can change also with the heat level during sintering reaction, even if it suppresses the fluctuation|variation of the component concentration of a sintering raw material, it is not necessarily able to suppress the fluctuation|variation of the component concentration of a sintering ore. For this reason, there existed a subject that the component concentration of the blast furnace raw material charged into a blast furnace could not be controlled to the target component concentration. The present invention has been made in view of the problems of the prior art, and an object thereof is to provide a blast furnace operating method capable of controlling the component concentration of the blast furnace raw material to a target component concentration even if the component concentration of the sinter raw material fluctuates is in doing

Characteristics of the present invention that solves these problems are as follows.

(1) A blast furnace operation method in which raw materials for a blast furnace including sintered ore, iron ore, and auxiliary materials are charged into a blast furnace, the sintering process of sintering the raw materials for sinter to make a sintered cake, and crushing the sintered cake into sintered ore A crushing process to, a cooling process for cooling the sintered ore, and a quadrant process of sieving the cooled sintered ore into a component sintered ore and a return ore, and the cooled sintered ore, the component sintered ore and a measuring step of measuring the concentration of at least one component of the semi-ore, and an adjusting step of adjusting a blending amount of the sintered ore, the lump iron ore and the auxiliary material contained in the blast furnace raw material; in the adjusting step, in the measuring step A method for operating a blast furnace, wherein the blending amount of the blast furnace raw material is adjusted using the measured component concentration.

(2) The blast furnace raw material further includes pellets, and in the adjusting step, the blending amount of the raw sintered ore, the pellets, the lump iron ore, and the auxiliary raw materials contained in the blast furnace raw material is adjusted, as described in (1). Blast furnace operation method.

(3) The blast furnace operation method according to (1) or (2), wherein in the measurement step, the concentration of at least one component of the cooled sintered ore, the original sintered ore, and the semi-luminous that is conveyed on a conveyor is continuously measured.

(4) The blast furnace operation method according to any one of (1) to (3), wherein in the measurement step, the concentration of at least one of the original sintered ore and the semi-gloss is measured.

(5) The blast furnace operation method according to any one of (1) to (3), wherein, in the measurement step, the component concentration of the original sintered ore is measured.

(6) The blast furnace operation method according to any one of (1) to (5), wherein in the measurement step, the _{concentration of one or more components of total CaO, SiO 2} , MgO, Al ₂ O _{3 and FeO is measured.}

By implementing the blast furnace operating method of the present invention, it is possible to control the component concentration of the blast furnace raw material to a target component concentration. Thereby, fluctuations in the viscosity of the blast furnace slag, etc. can be suppressed, thereby contributing to the stable operation of the blast furnace.

1 is a schematic diagram showing an example of a sintered ore manufacturing apparatus 10 capable of implementing the blast furnace operation method according to the present embodiment.
2 is a graph showing fluctuations in basicity of blast furnace slag.
3 is a graph showing fluctuations in coke ratio.
Fig. 4 is a graph showing fluctuations in basicity of blast furnace raw materials and fluctuations in coke ratio.
5 is a graph showing measured values of FeO concentrations in Inventive Example 3, Inventive Example 4, and Comparative Example 3. FIG.
6 is a graph showing the reduction amount of coke ratio in Inventive Example 3, Inventive Example 4, and Comparative Example 3. FIG.

(Form for implementing the invention)

In the present invention, a measurement step for measuring the component concentration of sintered ore is provided, and the component concentration of the sintered ore is measured in the measurement step. Using this component concentration, the blending amount of the blast furnace raw materials, such as sintered ore, pellets, lump iron ore, and auxiliary materials, is adjusted. In this way, it is possible to control the component concentration of the blast furnace raw material to become a target component concentration, and as a result, it has been found that the blast furnace operation can be stabilized, and the present invention has been completed. EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated through embodiment of this invention.

1 is a schematic diagram showing an example of a sintered ore manufacturing apparatus 10 capable of implementing the blast furnace operation method according to the present embodiment. The sintered ore manufacturing apparatus 10 includes a sintering machine 12 , a primary crusher 14 , a cooler 16 , a secondary crusher 18 , and a plurality of quadrants 20 , 22 , 24 , 26 . and an infrared analyzer 28 , a character line 30 , and a semi-luminous line 32 .

In the sintering machine 12, a sintering process is implemented. The sintering machine 12 is, for example, a downward suction type Dwight-Lloyd sintering machine. The sintering machine 12 has a sinter raw material supply device, a continuously moving pallet, an ignition furnace, and a wind box. A raw material for sinter is charged into a pallet from a sinter raw material supply device, and the charging layer of a sinter raw material is formed. The charging layer moves the combustion/dissolution zone in the charging layer below the charging layer by sucking the air in the charging layer downward through the windbox while being ignited in the ignition furnace. Thereby, the charging layer is sintered, and a sinter cake is formed. When suctioning the air in a charging layer downward through a windbox, you may supply the air which enriched gaseous fuel and/or oxygen gas from the upper direction of a charging layer. The gaseous fuel is any one combustible gas selected from blast furnace gas, coke oven gas, blast furnace/coke oven mixed gas, converter gas, city gas, natural gas, methane gas, ethane gas, propane gas, and these mixed gases.

In the primary crusher 14, a crushing process is implemented, and the sintered cake is crushed by the primary crusher 14, and turns into sintered ore. In the cooler 16, a cooling process is performed, the sintered ore is cooled by the cooler 16, and it turns into the cooled sintered ore.

In the quartering apparatuses 20 , 22 , 24 and 26 , a quartering process is performed. In the division apparatus 20, the cooled sintered ore is divided into a sintered ore having a particle diameter of more than 75 mm and a sintered ore having a particle diameter of 75 mm or less. In the present embodiment, the particle size means a particle size divided by a sieve, for example, sintered ore having a particle size of more than 75 mm is a particle size divided on a sieve using a sieve with a graduated interval of 75 mm, and a particle size of 75 mm or less Sintered ore means the particle size divided under the sieve using a sieve with a grid interval of 75 mm.

The sintered ore having a particle diameter of more than 75 mm divided on a sieve in the sieving device 20 is pulverized by the secondary crusher 18 so as to have a particle diameter of 50 mm or less. The pulverized sintered ore is mixed down a sieve, and is divided in a quadrant 22 . Thereby, the upper limit of the particle diameter of an original sintered ore can be made into 75 mm or less.

The sintered ore having a particle diameter of 75 mm or less divided under the sieve in the quadrant 20 is then quadranted in the quadrants 22, 24, 26 into sintered ore having a particle diameter of more than 5 mm and semi-light having a particle diameter of 5 mm or less. do. The component sintered ore divided by the division apparatuses 22 , 24 , 26 is conveyed to the blast furnace 34 from the belt conveyor which is the component line 30 . On the other hand, the semi-light divided by the division apparatuses 22 , 24 , 26 is conveyed to the sinter raw material supply apparatus of the sintering machine 12 again from the belt conveyor which is the semi-light line 32 . Each value of the particle diameter of the sintered ore, the particle diameter of the original sintered ore, and the particle diameter of the semi-light divided using the quadrants 20, 22, 24, and 26 is merely an example, and is not limited thereto.

An infrared analyzer 28 is formed on the belt conveyor of the product line 30 . In the infrared analyzer 28, a measurement process is performed. In the measurement process, the concentration of one or more components among _{total CaO, SiO 2} , MgO, Al ₂ O ₃ , and FeO contained in the original sintered ore is measured. The infrared analyzer 28 irradiates infrared rays having a wavelength within the range of 0.5 µm to 50.0 µm as sintered light, and receives reflected light from the sintered light. _{Since each molecular vibration of total CaO, SiO 2} , MgO, Al ₂ O ₃ , and FeO contained in the sintered ore absorbs the intrinsic wavelength component of the irradiated infrared, these components impart a unique wavelength component to the reflected infrared do. Therefore, it is possible to measure a component concentration of the total CaO, SiO _2, MgO, Al ₂ O _3, FeO in the sintered ore character by analyzing the irradiated light and the reflected light. Total CaO refers to the conversion of all the Ca compound having Ca and O, such as CaO, CaCO _3, Ca (OH) ₂ or Fe ₂ CaO ₄ to CaO.

The infrared analyzer 28 irradiates infrared rays with a wavelength of 20 or more at a frequency of, for example, 128 times per minute, and receives the reflected light reflected by the natural sintered light. By irradiating infrared rays for a short time in this way, the infrared analyzer 28 can continuously measure the component concentration of the sintered ore of the original product conveyed on the belt conveyor of the product line 30 on-line. The infrared analyzer 28 is an example of a component analysis device, and is not limited to a method of spectroscopy of reflected light, and a method of spectroscopy of transmitted light may be used. In addition, instead of the infrared analyzer 28, a laser analyzer that irradiates a laser as a measurement object, a neutron analyzer that irradiates neutrons as a measurement object, or a microwave analyzer that irradiates microwaves as a measurement object may be used.

The component sintered ore, whose component concentration has been measured, is returned to the blast furnace 34, and an adjustment step of adjusting the blending amount of the blast furnace raw material consisting of the component sintered ore, pellets, lump iron ore and auxiliary material is performed. The blast furnace raw material may contain raw materials other than the above, and may not contain pellets. In the adjustment step, the total component amount of the blast furnace raw material is calculated using the component concentration of the raw sintered ore measured using the infrared analyzer 28 and the component concentration of pellets, lump iron ore, and auxiliary materials measured in advance, and the calculated value is used Thus, feed-forward control is performed on the blending amount of the blast furnace raw material so as to achieve a target component concentration. For example, to control a component concentration of the blast furnace basicity (CaO / SiO ₂₎ of the raw material to the target, it will be sufficient to adjust the mixing amount of the additives contained in the blast furnace raw material.

For example, when the FeO concentration of the raw sintered ore increases and the FeO concentration of the blast furnace raw material increases, the reduction target of the blast furnace raw material deteriorates. When the reduction target of the blast furnace raw material deteriorates, indirect reduction, which is an exothermic reaction, decreases, and direct reduction, which is an endothermic reaction, increases, resulting in insufficient heat in the blast furnace. In order to eliminate this heat shortage, the coke ratio in blast furnace operation increases by further charging a reducing material into a blast furnace. For this reason, by controlling the FeO concentration of the blast furnace raw material to a target component concentration, an increase in the coke ratio in the blast furnace operation can be suppressed, and it is possible to contribute to the stable operation of the blast furnace. For example, in order to control FeO of a blast furnace raw material to the target component concentration, what is necessary is just to adjust the compounding quantity of the lump ore contained in a blast furnace raw material.

In this way, the blending amount of the blast furnace raw material is adjusted so that the component concentration of the blast furnace raw material becomes the target component concentration. In this embodiment, the measurement frequency of the component concentration by the infrared analyzer 28 is 128 times per minute, the average value of the component concentration of the 128 times is calculated once per minute, and the average value of the calculated component concentration is was used to adjust the blending amount of the blast furnace raw material every 1 minute.

As described above, in the blast furnace operating method according to the present embodiment, the component concentration of the component sintered ore conveyed through the component line 30 is measured using the infrared analyzer 28, and the component concentration is used to target the component concentration. Adjust the blending amount of the blast furnace raw material so that Accordingly, even if the component concentration of the sinter raw material fluctuates and the component concentration of the original sintered ore fluctuates, the component concentration of the blast furnace raw material can be controlled to the target component concentration, and the blast furnace operation is reduced by charging the blast furnace raw material into the blast furnace It is stable and can suppress the increase of the coke ratio in blast furnace operation.

In the present embodiment, the infrared analyzer 28 is formed on the belt conveyor of the sintered ore line 30 and an example of measuring the component concentration of the sintered ore is shown, but the present invention is not limited thereto. It may be formed in any one position in the apparatus 10, and you may measure the component concentration of at least 1 or more of the cooled sintered ore, an original sintered ore, and semi-luminous.

In the charging layer in which the raw material for sinter is charged into the pallet, the component concentration of the surface layer and the component concentration of the lower layer are largely different, and the component concentration fluctuates depending on the moisture content of the raw material for sinter and/or the state of the sintering raw material supply device. Analysis by infrared rays can analyze only the surface layer to be analyzed due to its properties. For this reason, the component concentration of the surface layer and the component concentration of the lower layer are different, and even if the charging layer in which this component concentration fluctuates with the infrared analyzer 28 is measured, the component concentration of the whole charging layer cannot be measured with high precision. On the other hand, after the cooling step, since the raw material for sinter is sintered, pulverized, cooled, and mixed to some extent, the component concentration in the surface layer and the component concentration in the lower layer do not differ significantly. For this reason, in the measuring process of this embodiment, the concentration of at least 1 component among the sintered ore after a cooling process, an original sintered ore, and semi-luminous is measured. Accordingly, even the infrared analyzer 28 that can analyze only the surface layer of the analysis target can measure the component concentration with high accuracy.

In the state where the particle size distribution of the sintered ore is wide, for example, as it is said that infrared rays cannot be irradiated to the sintered ore with a small particle diameter that is obscured by the sintered ore with a large particle diameter, only a part of the sintered ore can be irradiated with infrared rays, and the reflected light from the sintered ore is also not stable On the other hand, after the quadrant step, since the sintered ore having a particle diameter of more than 5 mm and a semi-bright having a particle diameter of 5 mm or less are divided, the particle size distribution of the sintered ore is narrow. For this reason, in a measurement process, it is preferable to measure the concentration of at least 1 component of the original sintered ore and semi-gloss after a quadrant process. Accordingly, the infrared analyzer 28 can uniformly irradiate infrared rays to the sintered light, and since the reflected light from the sintered light is also stable, the component concentration can be measured with higher precision.

After the quadrant process, the component concentration of the sintered ore or semi-gloss is measured in the measurement process, but measuring the sintered ore of the nature rather than measuring the semi-gloss is to directly measure the component concentration of the sintered ore used as one of the blast furnace raw materials. Because it can be, it is more preferable.

Example 1

Using the sintered ore manufacturing apparatus 10 in which the infrared analyzer 28 is formed on the original line 30, the total _{concentration of CaO, SiO 2} , MgO, Al ₂ O ₃ and FeO contained in the original sintered ore is measured in 1 minute. It measured at the frequency of 1 time. Invention example 1 is an operation example in which the compounding quantity of the auxiliary material of a blast furnace raw material was adjusted at the frequency of 1 time per minute using the said measurement result. Comparative Example 1 is an operation example in which the blending amount of the auxiliary material of the blast furnace raw material is not adjusted. The fluctuations in the basicity of the blast furnace slag and the coke ratio of the blast furnace in Comparative Example 1 and Invention Example 1 were measured.

2 is a graph showing fluctuations in basicity of blast furnace slag. Fig. 2(a) shows the fluctuation of the basicity of Comparative Example 1, and Fig. 2(b) shows the fluctuation of the basicity of the Invention Example 1. In FIG. 2 , the horizontal axis represents time (days), and the vertical axis represents total CaO/SiO ₂ (−). The basicity value shown in FIG. 2 is a value measured by performing off-line chemical analysis of the components of the molten iron and blast furnace slag extracted from the blast furnace.

As shown in Fig. 2, in Comparative Example 1, the basicity was largely irregular in the vicinity of the target value. On the other hand, in Invention Example 1, the component concentration of the original sintered ore is measured at a frequency of once per minute, and the composition of the blast furnace raw material is adjusted so that the component concentration of the blast furnace raw material becomes a target value using the component concentration, so that the basicity deviation from the target value of Thus, it was confirmed that the deviation from the target value of the basicity in the blast furnace slag can be reduced by implementing the blast furnace operating method according to the present embodiment.

3 is a graph showing fluctuations in coke ratio. In FIG. 3 , the horizontal axis represents time (days), and the vertical axis represents coke ratio (kg/t-pig). 0 to 19 days are the coke ratio of Comparative Example 1 in which the blast furnace operation was performed by charging the blast furnace raw material for which the blending amount is not adjusted, and 20 to 39 days are the blast furnace raw materials in which the blending amount is adjusted at a frequency of once per minute. It is the cokesby of Invention Example 1 in which the blast furnace operation was performed by charging.

As shown in FIG. 3 , compared with Comparative Example 1, the coke ratio in the blast furnace operation was lower in the invention example 1 . Thus, by implementing the blast furnace operation method which concerns on this embodiment, blast furnace operation was stabilized, and as a result, it was confirmed that the increase in the coke ratio of blast furnace operation could be suppressed.

Example 2

Fig. 4 is a graph showing fluctuations in basicity of blast furnace raw materials and fluctuations in coke ratio. Fig. 4(a) shows fluctuations in the basicity of the blast furnace raw materials of Comparative Example 2 and Invention Example 2. In Fig. 4(a) , the horizontal axis represents time (hours), and the vertical axis represents total CaO/SiO ₂ (−) of the blast furnace raw material. Fig. 4(b) shows the fluctuation of the coke ratio of the blast furnace operation of Comparative Example 2 and Invention Example 2. In Fig. 4(b), the horizontal axis is time (hours), and the vertical axis is coke ratio (kg/t-pig).

In Fig. 4, Comparative Example 2 uses fluorescent X-rays to _{measure total CaO and SiO 2} of the original sintered ore at a frequency of once every 2 hours, and using the measurement result, the auxiliary raw material of the blast furnace raw material is the same at the same frequency. It is an operation example in which the compounding quantity of was adjusted. In Invention Example 2, in the same manner as Inventive Example 1, using the infrared analyzer 28 formed in the product line 30, the total CaO and SiO ₂ component concentrations of the original sintered ore are obtained at a frequency of once per minute, and the measurement is performed. It is an operation example in which the compounding quantity of the auxiliary material of a blast furnace raw material was adjusted at the same frequency using the result.

In the example shown in FIG. 4, the blast furnace operation was performed under the conditions of the comparative example 2 from 0 to 6 o'clock, and the blast furnace operation was implemented under the conditions of the invention example 2 from 6 o'clock to 19:00. As shown in Fig. 4(a), in Comparative Example 2 as well, since the blending amount of the auxiliary material is adjusted at a frequency of once every 2 hours, the change in the basicity of the blast furnace raw material is suppressed in the measurement once every 2 hours. see. However, as a result of changing from Comparative Example 2 to Invention Example 2 and adjusting the blending amount of the auxiliary material of the blast furnace raw material at a frequency of once per minute, as shown in FIG. The cokes ratio of the blast furnace operation fell from the time period considered to be charged. In general, the sintered ore discharged from the sintering machine is cooled by a cooler, and after being established, it is charged into the blast furnace via the ore bin of the blast furnace. Although depending on the size of the low light tank, the residence time of the raw material in the low light tank used in this example is about 8 hours, and it can be inferred that the effect gradually appeared in the blast furnace after 8 hours.

From this point of view, it seems that the fluctuation of the basicity is suppressed in the measurement once every 2 hours, but the basicity of the blast furnace raw material fluctuates during that time. On the other hand, in Invention Example 2, the infrared analyzer 28 is formed in the _{raw material line 30, the total CaO and SiO 2} of the raw sintered ore are measured at a frequency of once per minute, and the measurement result is used to determine the raw material of the blast furnace. Since the blending amount of the auxiliary material was adjusted so that the basicity became the target value, the fluctuation of the basicity of the blast furnace raw material was suppressed even within 2 hours, and as a result, it is considered that the increase in the coke ratio of the blast furnace operation was suppressed.

Example 3

5 is a graph showing measured values of FeO concentrations in Inventive Example 3, Inventive Example 4, and Comparative Example 3. FIG. In FIG. 5, the vertical axis|shaft is the measured value (mass %) of the FeO density|concentration in a certain specific time.

In Invention Example 3, the infrared analyzer 28 is formed in the product line 30, and the total _{concentration of CaO, SiO 2} , MgO, Al ₂ O ₃ and FeO of the original sintered ore is measured at a frequency of once per minute, , is an operation example in which the blending amount of the auxiliary material of the blast furnace raw material is adjusted at a frequency of once per minute using the measurement result. In Invention Example 4, the infrared analyzer 28 is formed on the semi-luminous line 32, and the total _{concentration of CaO, SiO 2} , MgO, Al ₂ O ₃ and FeO of the sintered ore is measured at a frequency of once per minute. , is an operation example in which the blending amount of the auxiliary material of the blast furnace raw material is adjusted at a frequency of once per minute using the measurement result. In Comparative Example 3, the infrared analyzer 28 is formed at a position where the surface of the sinter cake of the sintering machine 12 can be measured, and the total CaO, SiO ₂ , MgO, Al on the surface of the sinter cake is performed at a frequency of once per minute. _{This is an operation example in which the component concentrations of 2} O ₃ and FeO are measured, and the blending amount of the auxiliary material of the blast furnace raw material is adjusted at a frequency of once per minute using the measurement result.

As shown in FIG. 5, the FeO density|concentration at the time of measuring the semi-light produced from the same sintering raw material was 6.9 mass % to the case where the FeO density|concentration at the time of measuring the original sintered ore was 7.1 mass %. From this result, there was no significant difference between the result of measuring the FeO concentration of the semi-light using an infrared analyzer and the result of measuring the FeO concentration of the original sintered ore. On the other hand, the FeO concentration at the time of measuring the surface of the sinter cake which sintered the same sintering raw material using the infrared analyzer 28 was 5.6 mass %, and it differed greatly from the FeO density|concentration at the time of measuring the raw sintered ore.

An infrared analyzer can measure only the component concentration of the surface irradiated with infrared rays due to its nature. Since the original sintered ore or semi-glow is crushed and mixed to some extent in the process, the average component of the whole can be obtained by irradiation of infrared rays to the surface. On the other hand, since the component concentration of the raw material for sinter charged into the pallet is different between the upper layer and the lower layer, and the heat level of the upper layer and the lower layer during sintering is different, there is a big difference in the component concentration between the upper layer and the lower layer of the sintering cake. For this reason, as shown in FIG. 5, it is thought that the component concentration of the comparative example 3 which measured the surface of the sintered cake with an infrared analyzer differed greatly from the component concentration of the invention example 3 which measured the surface of the original sintered ore.

6 is a graph showing the reduction amount of coke ratio in Inventive Example 3, Inventive Example 4, and Comparative Example 3. FIG. In Fig. 6, the vertical axis is the amount of cokes ratio reduction (kg/t-pig). The reduction amount of the coke ratio shown in FIG. 6 is normal, before the adjustment of the blending amount of the blast furnace raw material, and after adjusting the blending amount of the blast furnace raw material by Inventive Example 3, Inventive Example 4, and Comparative Example 3, the influence of operational fluctuations subsides, and is normal It is the amount of reduction of cokesby after 120 hours presumed to have been operated under the conditions.

Inventive Example 3, in which the blending amount of the auxiliary material of the blast furnace raw material was adjusted using the component concentration of the original sintered ore charged into the blast furnace as the blast furnace raw material, and the component concentration of the semi-gloss that does not differ from the component concentration of the original sintered ore. In the invention example 4 in which the compounding quantity was adjusted, the coke ratio at the time point after 120 hours passed decreased. On the other hand, in Comparative Example 3, in which the blending amount of the auxiliary material of the blast furnace raw material was adjusted using the measured value of the sinter cake having a large difference in component concentration and the original sintered ore charged into the blast furnace, the coke ratio at the time point after 120 hours had elapsed was increased. . This is considered to reflect the result that in Comparative Example 3, the component concentration of the blast furnace raw material charged into the blast furnace was not adjusted to the target component concentration.

10: sinter ore manufacturing device
12: sintering machine
14: primary crusher
16 : cooler
18: secondary crusher
20: quadrant device
22: quadrant device
24: quadrant device
26: quadrant device
28: infrared analyzer
30: character line
32: semi-gloss line
34: blast furnace

Claims (7)

A method of operating a blast furnace for charging a blast furnace raw material including sintered ore, iron ore, and auxiliary raw materials into a blast furnace,
A sintering step of sintering the sintering raw material to make a sintered cake;
A crushing process of crushing the sintered cake into sintered ore;
a cooling process of cooling the sintered ore;
A quadrant process of dividing the cooled sintered ore into a characteristic sintered ore and a return ore;
A measuring process of continuously measuring the concentration of at least one of the cooled sintered ore, the raw sintered ore, and the semi-gloss conveyed on a conveyor online using an infrared analyzer, a laser analyzer, a neutron analyzer, or a microwave analyzer;
an adjustment step of adjusting the blending amount of the sintered ore, the lump iron ore, and the auxiliary material contained in the blast furnace raw material;
In the adjusting step, the blending amount of the blast furnace raw material is adjusted so that the component concentration of the blast furnace raw material becomes a target component concentration by using the fluctuating component concentration continuously measured in the measuring step. According to claim 1,
The blast furnace raw material further includes pellets,
In the adjusting step, the blending amount of the raw sintered ore, the pellets, the lump iron ore, and the auxiliary material contained in the blast furnace raw material is adjusted. 3. The method of claim 1 or 2,
In the said measuring process, the blast furnace operation method of measuring the component concentration of at least 1 of the said sintered ore of the said nature and the said semi-gloss. 3. The method of claim 1 or 2,
In the said measuring process, the component concentration of the said sintered ore is measured, the blast furnace operation method. 3. The method of claim 1 or 2,
A blast furnace operation method in which the concentration of one or more components among total CaO, SiO ₂ , MgO, Al ₂ O _{3 and FeO is measured in the measurement step.} 4. The method of claim 3,
A blast furnace operation method in which the concentration of one or more components among total CaO, SiO ₂ , MgO, Al ₂ O _{3 and FeO is measured in the measurement step.} 5. The method of claim 4,
A blast furnace operation method in which the concentration of one or more components among total CaO, SiO ₂ , MgO, Al ₂ O _{3 and FeO is measured in the measurement step.}

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